I think you're making a big stink out of nothing, what is not to work? The lens provides the camera with its FL, one assumes the TC alters the FL and therefore SR will be on par with the FL. Honestly with my testing its better to have the SR a little weaker than par with the focal length if you want more SR stops at long FLs. Its not likely AF will change, 90% of third party lenses are still screw drive, screw drive TC's still work fine, one would assume Pentax did the SDM correctly too so nothing to fail there. about the only area where things might fail is the in lens corrections but they don't even exist for third party lenses. so correct ID or not what what will go wrong that isn't already wrong before the TC is available?